This invention relates to grafts for use in the repair, replacement, or supplement of a medical patient's natural body organ structures or tissues. The invention also relates to methods for making graft structures. The invention further relates to methods and apparatus for delivering a graft to an operative site in a patient, and for installing the graft at that site. Some aspects of the invention may have other uses such as for viewing the interior of a patient, providing access to the interior of a patient for other procedures, etc. An example of the possible uses of the invention is a minimally invasive cardiac bypass procedure. This example will be considered in detail, but it will be understood that various aspects of the invention have many other possible uses.
Several procedures are known for revascularizing the human heart in order to treat a patient with one or more occluded coronary arteries. The earliest of these procedures to be developed involves exposing the heart by means of a midline sternotomy. Following surgical exposure of the heart, the patient's aorta and vena cava are connected to a heart/lung machine to sustain vital functions during the procedure. The beating of the heart is stopped to facilitate performance of the procedure. Typically, a suitable blood vessel such as a length of the patient's saphenous (leg) vein is harvested for use as a graft. The graft is used to create a new, uninterrupted channel between a blood source, such as the aorta, and the occluded coronary artery or arteries downstream from the arterial occlusion or occlusions.
A variation of the above procedure involves relocating a mammary artery of the patient to a coronary artery.
Although the above-described sternotomy procedures are increasingly successful, the high degree of invasiveness of these procedures and the requirement of these procedures for general anesthesia are significant disadvantages. Indeed, these disadvantages preclude use of sternotomy procedures on many patients.
More recently, less invasive procedures have been developed for revascularizing the heart. An example of these procedures is known as thoracostomy, which involves surgical creation of ports in the patient's chest to obtain access to the thoracic cavity. Specially designed instruments are inserted through the ports to allow the surgeon to revascularize the heart without the trauma of a midline sternotomy. Drugs may be administered to the patient to slow the heart during the procedure. Some thoracostomy procedures involve relocating a mammary artery to a coronary artery to provide a bypass around an occlusion in the coronary artery.
Thoracostomy bypass procedures are less traumatic than sternotomy bypass procedures, but they are still too traumatic for some patients. Also, the number of required bypasses may exceed the number of mammary arteries, thereby rendering thoracostomy procedures inadequate to fully treat many patients.
Another technique for revascularizing the human heart involves gaining access to the thoracic cavity by making incisions between the patient's ribs. This procedure is known as thoracotomy. It is also substantially less traumatic than midline sternotomy, but it is still too traumatic for some patients.
In view of the foregoing, it is an object of this invention to provide less traumatic methods and apparatus for revascularizing a patient.
It is another object of the invention to provide minimally invasive methods and apparatus for repairing, replacing, or supplementing the blood vessels or other body organ tubing or tissues of a patient.
It is still another object of the invention to provide improved graft structures for use in the repair, replacement, or supplementing of natural body organ structures or tissues, and to provide methods for making such graft structures.
It is yet another object of the invention to provide improved methods and apparatus for transporting or delivering and installing graft structures for use in the repair, replacement, or supplementing of natural body organ structures or tissues of a patient.